


dress up

by pleasurific



Series: temptation [5]
Category: Teen Wolf (TV)
Genre: Age Difference, Babysitter Derek Hale, Blow Jobs, Dubious Consent, Dubious Morality, Extremely Underage, Feeding, M/M, Nudity, Shota, Shota Stiles Stilinski, Stiles is nine, Teasing, Underage Sex, derek is fifteen
Language: English
Status: Completed
Published: 2018-11-18
Updated: 2018-11-18
Packaged: 2019-08-25 15:21:42
Rating: Explicit
Warnings: Underage
Chapters: 1
Words: 2,594
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/16663321
Author URL: https://archiveofourown.org/users/pleasurific/pseuds/pleasurific
Summary: Time goes by and autumn brings falling leaves, cool weather and... Halloween. Which comes with costumes. And Stiles, naturally, wants to be Batman.





	dress up

**Author's Note:**

> **PLEASE READ THE TAGS CAREFULLY before reading**
> 
> This part is more plotty than others. It's part of a series and the other parts provide extra context.

The leaves start changing colors and Derek spends less time outside as it gets colder. Not that he minds, since he spends most of the time either at basketball practice or at the Stilinski's, his presence almost constant as the Sheriff gets used to relying on Derek's babysitting services. Laura teases him about it a little, about how fond he's grown of Stiles -- not that she knows just _how_  fond. 

But with autumn comes Halloween and Stiles's costume planning for trick-or-treating. Derek gets to go roaming through the mall's costume shops and then roped into elaborate explanations of what Stiles _needs_  his costume to be on the day. 

"I can't just wear tights, Derek!" Stiles exclaims when Derek tries to suggest a cheaper solution to the elaborate options that they've seen in the shops. 

He knows that the Sheriff isn't flush with money and he knows better than to suggest that he'll pay for Stiles's costume. Not even his mom tries to do that, even though she's grown fond of Stiles herself -- Derek had him over a few times when he picked him up from school. Stiles would accept the offer, his longing for the perfect costume bigger than his pride about being able to get it himself. 

"I didn't say _tights_ ," Derek protests. "I just said that we could maybe find a way to _make_  the costume, instead of spending money on something you won't even fit into in a month." 

Stiles has grown lately, but not enough to make a world of difference. He's still shorter than Derek and still thin, all arms and legs as he tends to prove when he wraps himself around Derek at the most inconvenient of times. Like now, when they're waiting for Laura to drive them back home from the mall and Stiles is on Derek's back after insisting that his feet hurt. His arms are wrapped around Derek's neck, legs in a vice on Derek's sides and his chest is pressed into Derek's back. Which means that Derek, despite wearing a jacket, can feel everything, including Stiles's little cock pressed into his lower back. 

He does like the excuse of having his hands on Stiles's butt under the guise of holding him up, since Stiles wiggles a lot even as he's holding on tight. Derek wonders if Stiles wore the thin, worn-out pants on purpose, but then shakes the thought off because Stiles doesn't yet have the planning ability when it comes to being a tease. He is one, there's no doubt about that, but he does those things without realizing what they do to Derek most of the time. Like when he greets Derek with a tackling hug on some of the babysitting nights. Or when he decides that he wants to find out if he can eat a whole banana in one go. 

That one almost made Derek come without any sort of physical contact at all. 

Stiles, of course, almost choked, but insisted that one day he was going to manage. 

Right now, it's only the heat of his body and the closeness that's making Derek need to focus on the fact that his sister is about to show up and he has to _not_  smell like he's turned on. Luckily, Stiles burps into his ear just then, a result of the fizzy drinks they had with their food earlier, and Derek makes a face, forgetting all about his hardening cock. It's a close call and he knows that Laura can still smell the remnants of his arousal.

"Weren't you here to watch _him_ , instead of ogling girls?" Laura asks when they get in the Camaro, after telling Stiles that no, he can't sit in the front. 

Derek rolls his eyes and feels his cheeks burn, but doesn't say anything. After all, it's not like he noticed anyone but Stiles all afternoon. 

The rambling about his costume continues as they drive to the Stilinski house where Derek is again staying for the night. 

"I'm sure you guys will figure something out," Laura says as she drops them off. "Batman had to _make_  his costume at first too, didn't he?" 

Stiles's eyes light up and he grins at her, then bounces off towards the house without waiting for Derek.,

"Good luck," Laura says, then she smirks and drives off. 

When Derek gets in -- Stiles dashed right inside after digging the spare key from the flower pot -- he's met with silence at first, then thuds coming from Stiles's room. He sighs and heads upstairs, only barely noticing the containers with leftovers on the table as he passes the kitchen. 

Opening the door to Stiles's room brings a whole different shock. Stiles has somehow managed to lose all his clothes and he's darting around the room between his wardrobe and his bed, making a small pile on top of the sheets. 

"Stiles, what are you doing?" Derek asks, knowing that he sounds out of breath as he always does at the sight of Stiles's body. 

"Making a costume," Stiles says, not stopping. 

"Why do you need to be _naked_  for that?" 

"Because I'm gonna try it on," he says, the "duh" implied in his tone. "Be back!" 

Derek watches him dash out of the room and towards the spare one at the back, where he knows the Sheriff stores old things, like some clothes that used to belong to his wife that he hasn't had the heart to give away yet. Stiles comes back with an armful of dark pieces, among them a leather jacket that's entirely too big. And a pair of leather pants. 

"Stiles, baby, there's no way these are going to fit," Derek tells him and he finally steps fully into the room. 

His eyes are on Stiles's butt, on the dips on his lower back just above the bubbly cheeks, on the cleft that opens when Stiles bends forward to lay out the clothes the way he wants to. 

"Imma need padding," Stiles says a beat later. "Then they'll fit. Mama was short."

Derek remembers Mrs Stilinski only vaguely, but enough to know that Stiles is right. She wasn't particularly tall and she was thin. 

"Also, they're elastic," Stiles points out, holding up the pants in front of him and stretching them out to prove his words. 

"Right, so, what are we doing here," Derek says, glancing over the clothes on the bed. 

Stiles shrugs, then he grabs the few pieces he decided were necessary and runs off into the bathroom. When he comes out, he's wearing a black tee, the leather-like pants that obviously had other clothing stuffed into them and make Stiles's skinny legs look bulky in unnatural ways, and the leather jacket that looks way too big on his slender frame. 

"I already have a mask for the face," he says proudly. "What do you think?" 

Derek watches as Stiles turns around, showing off the makeshift costume. 

"You'll need a cape," he says, not able to say anything else. 

"I can make that, I have a black sheet that Dad said I could use," Stiles answers. 

A beat later, Derek walks up to him and kneels in front of Stiles, slipping his hands under the black leather and onto Stiles's hips. 

"You know, this doesn't really work and can't be comfortable," he says, sliding his hands down over the bulky parts of Stiles's pants. "Maybe I could be your Alfred and fix it so the pants fit you right."

"But then I won't be all muscly like Batman," Stiles says with a pout.

"I don't know, I think you look just fine the way you are," Derek tells him, looking up at Stiles's face. “It would look a lot nicer if they were fitting. And you'd be able to move around easier."

He thinks about how the pants would hug Stiles's butt just right, how they could fit around his slim legs perfectly. He tries and fails to _not_  think about Stiles in skin-tight black clothes, bouncing around like he tends to. 

"I can do that in Home Ec. We're doing sewing this month anyway," he offers.

Stiles's face lights up and that's that, Derek's won that fight. 

"Now, let's get you out of these so I can put them in my bag." 

The jacket and top are off in a flash, then Derek tugs out the old tees that Stiles stuffed into the pants and lowers the leather down Stiles's legs. He's still on his knees in front of him and ends up face to face with Stile's crotch.

"You didn't wear undies?" 

Stiles shakes his head, puffing up his chest. 

"Batman wouldn't."

"Well, I'm not so sure about that," Derek says, but his mind is already elsewhere. 

He leans forward and plants a kiss right above Stiles's cocklet, then another one on its soft flesh. Stiles's knees wobble a little but he doesn't move, his eyes wide open as he looks down at Derek. 

"Come on, we should get some dinner," Derek says, standing up. "Your dad left some food out." 

Stiles looks up, then down at Derek's crotch, like he wants to ask for something else in his mouth. He doesn't, in the end, but he rushes out of the room before putting on clothes. Derek chases after him all the way downstairs and finds Stiles poking at the containers that clearly hold leftovers. He makes a face at them and then looks at Derek, his lips in a pout.

"I'm not ordering pizza," Derek says, before Stiles can open his mouth. "Am I gonna have to feed you?" 

Stiles crosses his arms over his chest and stands there in all his naked glory, his expression defiant. Derek glances at the open containers, then grabs one and heads to the microwave to warm it up. Stiles doesn't move an inch while Derek gets a fork and then when he brings the food to the table. 

"Right, come on," Derek says.

He walks up behind Stiles, easily lifts him up with an arm around his narrow waist, then he sits down with Stiles in his lap, both of them facing the table. Stiles squirms, his naked butt rubbing over Derek's jean-clad crotch where his cock is rapidly hardening right under Stiles's own. 

"If you think I'm not gonna feed you, you're wrong," Derek says when Stiles wiggles again. "Come on, open up." 

Stiles, to Derek's surprise, obediently opens his mouth. He doesn't stop moving while they continue like this, with Derek feeding him the casserole from the Tupperware until most of it is gone. 

"Enough," Stiles says eventually, rubbing his stomach. "So full." 

"Are you?" Derek asks with a teasing lilt. "No treats after dinner then?" 

Stiles wiggles until he's turned around and facing Derek, his legs wrapped around Derek's hips. 

"There's a treat?" 

Derek grins and moves his hips, knowing that Stiles won't miss the hardness pushing against his cleft. 

"I don't know, do you deserve one?" 

Stiles's eyes open wide and he runs his tiny tongue over his lips, then pulls his bottom lip between his teeth. 

"I think maybe you do," Derek says. 

He pushes the chair further from the table and stands up, bringing Stiles with him, hands on his bubble butt, fingers already spreading his cheeks. He knows that Stiles can feel the air brushing over his hole because he feels the boy's body shiver. Stiles wraps his arms around Derek's shoulders and nuzzles his face into the crook of Derek's neck. They head upstairs like this, with Stiles's nude body pressed against Derek's chest, a reminder of why Derek finds it hard to keep calm when Stiles does this if they're in front of others. 

Derek's jeans feel too tight, so he reaches down and opens the button and zipper while they're still walking and his cock springs up, brushing against Stiles's butt, right along the cleft. Stiles whimpers against him then he lets out a little moan when Derek puts his fingers back on the butt cheeks, spreading them open again. By the time they get to Stiles's room and he leans over -- Stiles never lets go, just holds on tighter -- to toss the clothes off Stiles's bed, Derek doesn't want to move. He wants to stay like this, rub his cock between Stiles's cheeks, feel it catching on the rim of the tight hole, pretend for a while that he _could_  push inside. 

Stiles has other ideas though and he squirms away from Derek, then crawls on the bed and sits with his legs bent, butt between his ankles. His eyes are focused on Derek's crotch and he parts his lips. 

"So this is a treat then?" Derek asks, stepping closer, his toes hitting the bed. 

Stiles nods and leans forward, bracing his hands on his parted knees. Derek smiles and wraps his fingers around his cock, then moves his hips forward until he can rub the tip of the cock over Stiles's bottom lip. Stiles hums when he follows the movement with his tongue, licking up the drop of precome that Derek smeared over the lip. Then he leans forward and closes his lips over the head of Derek's cock and sucks, then swirls his tongue around it, poking at the glans right under it. Derek's hips jerk forward, but he aborts the movement, afraid to push too far into Stiles's mouth. 

He apparently doesn't need to worry about that, because the next thing Stiles does shows him just that. Stiles opens his mouth wide and leans in, basically falls right on Derek's cock, and takes about half of it into his mouth, his nose hitting Derek's fingers that are still holding his cock. Derek doesn't let go, he uses the fingers to hold off coming right there and then, the sight of Stiles's lips stretched around his cock almost too much to handle.

"You've been practicing, have you?" Derek asks, his voice rough. 

Stiles hums around his cock, sending vibrations down Derek's whole body. Then he sucks again, pulls off, swirls his tongue, then leans in again to swallow around half of Derek's length. Eventually, it becomes hard to keep his balance and Stiles lifts his arms and braces himself on Derek's hips instead of his own knees. Once he's steady, he goes back to licking and sucking, his little fingers digging into Derek's hips as he sucks and swallows every spurt of precome that drips out of Derek's cock right into his small mouth. Derek's barely managing to stay upright, but he holds on and lets go of his cock to put one hand on Stiles's shoulder and the other on the nape of his neck. 

He doesn't thrust forward, but soon he feels his balls tighten and his cock throb in Stiles's mouth. That's when he pushes Stiles off, earning himself a pout again.

"Open up, baby," Derek manages to say as he grips his cock again and strokes it once, twice, then feels his balls tense as come spurts all over Stiles's eager face. 

He catches his breath only to look at Stiles's come-covered face, his lips still parted and his pink tongue swiping all around them, pulling Derek's come into his mouth. His eyes are closed, drops of come caught on his dark eyelashes and sliding down his face onto the rest of his body, including his little cocklet that's twitching as Stiles's chest rises and falls. 

Derek thinks he's never seen him look more beautiful. Stiles might think this is a treat for him, but it's definitely one for Derek too. 

**Author's Note:**

> I'm on [tumblr](https://pleasurific.tumblr.com/) too!


End file.
